| Vertical-cavity surface-emitting laser(VCSEL) was first proposed in 1977 by Prof. Kenichi Iga from Tokyo Institute of Technology, which has less than 40 years. It is a new type of semiconductor laser with some advantages such as laser beam perpendicular to the substrate, on-chip testing, low threshold current, high modulation, single longitude mode and easy-to-fiber coupling owing to circular beam profile, which have widely used on data transmission, optical interconnection, gas detection and other applications.Since the multi-transverse mode VCSEL can be realized simultaneously lasing, while the multimode fiber-based optical interconnect system could require multiple transverse mode laser must be able to work, in order to reduce the bit error rate patterns caused by noise, so the multi-transverse mode VCSEL can be applied in large scale multimode fiber optic interconnection systems. And so far the country in a short distance optical communication system modeling aspects still remain blank, so much significance can be stable transverse mode VCSEL output profound.Often we want to single mode VCSEL, because the multi transverse mode oscillation will cause an increase in noise and line broadening, while the divergence angle of the VCSEL will increase rapidly, affecting the coupling efficiency of the device and fiber. VCSEL transverse modulus will change with the pumping conditions and thermal effects of change, especially with the different injection currents generated revenue patterns, thus affecting the optical output characteristics. However, locking the transverse mode after clamping the VCSEL can be used as an almost jitter-free source of timing signals, can be applied to the optical clock and optical frequency comb. Therefore, the study of multi-transverse-mode-locked VCSEL is a hot topic. The main research contents of this dissertation as follows: 1. Using Matlab software simulation of the standard circular symmetry oxide-confined VCSEL transverse mode distribution, and calculate its spectral characteristics. Obtained by the simulation, when the oxide aperture is circular, VCSEL multitransverse mode lasing will equally spaced arranged, when the pore size 8μm VCSEL oxide pattern space distance of 0.64 nm, and when the oxidation is increased to 20μm aperture when the mode VCSEL spatial distance was reduced to 0.25 nm, i.e. mode spatial distance decreases with increasing pore size. 2. Using Rsoft to landscape mode oval aperture VCSEL oxidation were simulated light field BPM algorithm based software. Obtained by the simulation, when the low mode order, not significantly different from the distribution of transverse mode, and when the higher order mode, the transverse mode VCSEL elliptical distribution more together, the distribution pattern in the minor axis direction is restricted seriously, energy distribution is uneven. 3. The combination of round and oval VCSELDE spectral model refractive index distribution model to calculate the spectral characteristics of the elliptical aperture VCSEL of oxidation. The simulation results show that the phenomenon is due to the anisotropy of the distribution of wavelength division oval produce a direct result of the refractive index between adjacent mode wavelength becomes non-equally spaced, and decreases the oxidation aperture and wavelength division will further increase the extent of the maximum wavelength split value of up to 0.037 nm. 4. A process for the preparation of different pore size on the(4μm-16μm) circular aperture VCSEL device and a partial oxidation oval oxidation aperture VCSEL device, test its output power, voltage, threshold current, slope efficiency, near-field mode distribution and spectral properties analyze its variation. Indirect experiments measured the difference in wavelength spacing of about 0.04 nm, this calculation is consistent with our results. |
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